1. Field of the Invention
The invention relates to a pressure vessel, more particularly to a pressure vessel including a clamping member that presses two sealing rings against a tubing connector and an inner liner, respectively.
2. Description of the Related Art
A pressure vessel can be used for storing drinking water and for providing a stable supply of the drinking water. The pressure vessel normally includes an outer shell of a metallic material, and an inner liner of a plastic material, such as polypropylene (PP), attached to an inner surface of the outer shell for preventing the drinking water from being contaminated by the metallic material.
U.S. Pat. No. 8,348,085 discloses a conventional pressure vessel that includes: an outer shell of a metallic material that defines an accommodating space therein; an inner liner of a plastic material that is attached to an inner surface of the outer shell; a flexible diaphragm disposed in the accommodating space; a through-wall connector that has an inner tubular portion and an exposed tubular portion which is welded to and extends outwardly from an exterior of the outer shell; and an anti-leakage assembly that is disposed between the inner liner and a neck section of the through-wall connector. The neck section of the through-wall connector is bent to hold the anti-leakage assembly against an interior of the inner liner. The inner tubular portion of the through-wall connector extends from the exposed tubular portion through the outer shell and the inner liner and into the accommodating space.
Since the inner liner is made from the plastic material, the through-wall connector is required to be welded to the outer shell before insertion of the inner liner into the outer shell so as to prevent softening and deformation of the inner liner due to the heat generated by the welding if the inner liner is inserted into the outer shell before the welding of the through-wall connector to the outer shell. As a consequence, insertion of the inner liner into the outer shell after the welding of the through-wall connector can be severely interfered by the inner tubular portion of the through-wall connector, which results in difficulty in assembling the inner liner with the outer shell and which can cause damage to the inner liner when the inner liner passes over the inner tubular portion of the through-wall connector.